Sotjud-bepkoducistg mechanism



Sept. 11, 1928.

E. U. IWWERKS SOUND REPRODUCING MECHANISM Filed June 18, 1.926

INVENTOZ Earl 11 1 wwer 5 A TTORNEY Patented Sept. 11, 1928.

UNITED STATES 1,684,098 PATENT OFFICE.

EERT U. IWWERKS, OF KANSAS CITY, MISSOURI.

SOUND-REPRODUCING MECHANISM.

Application filed June 18, 1026 Serial No. 116,898

- mechanism to amplify the vibrations in such a manner as to obtain the desired volume of sound therefrom. Said reproducing means preferably comprises a plurality of elongated vibratory members which are preferably rigid and are rod-like metallic men bers in the preferred form, which are mounted upon a sound box and which are connected with the stylus in such a manner that the vibrations are transmitted to said vibratory members and from said vibratory members to the sound box. It has been found that with this arrangement the undesirable distortion of the sound waves due to passing through the usual amplifying horn is avoided, particularly in connection with the musical. instruments and especially with the reproduction of the sounds produced by stringed musical instruments.

It is a further purpose of my inventionto provide means. for mounting said elongated vibratory members in sets, one of said sets comprising members appreciably longer than the members of the other of said sets, and to provide means for firmly mounting said members in fixed position on the sound box.

It is still another purpose of my invention to provide means for preventing the elongated vibratory members from vibrating in dependently of the sound vibrations trans- -mitted through the same at their individual vibration rates which would produce undesirable sounds injuring the tone quality of the sounds that are being reproduced. This is preferably accomplished by providing adj ustable tone controlling members which may be moved lengthwise of said vibratory members to such positions as to break up the natural period of vibration of said elongated members and prevent the same from vibrating at their natural rates of vilu'atiolr Other objects and advantages of the invention will appear as the description of the arompmnying drawings proceeds. However, I desire to have it distinctly understood that I do not intend to limit mvself to the exact details shown or described, but that I intend to include as part of my invention all such obvious changes and modifications of parts as would occur to a person skilled in this art and as would fall within the scope of the claims.

In the drawings:

Fig. 1 is a perspective view of a portion of a phonograph cabinet, showing my improved sound reproducing means in position thereon.

Fig. 2 is a side elevational view of my' braced by means of the diagonally extending members 14 and between which are mounted the transversely extending members 15 from which the projecting fingers 16 extend toward the side wall of the cabinet 10 to hold. the vertically extending portions of the brackets 11 substantially parallel to the side wall of the cabinet 10. Extending between the transversely extending members 15 is a pair of strips 17 which are spaced so as to provide a guide slot 18 between the same. Mounted in the guide slot 18 is the threaded end portion 19 of a rod-like member or stem 20, the same being held in adjusted position in the slot 18 by means of the nut 21 on one side of the members 17 and the wing nut 22 on the other side of the members 17.

The rod-like or stem member 20 is received within a socket member 23 provided on the lower end of the yoke 24 having a pair of substantially parallel, upwardly extending arms 25 carrying a transverse pivot pin 26 upon which the sound box member 27 is pivotally mounted.

d. The sound member 217' preferably i so ori'linarily made.

made of wood and oil? the general shape of a stringed musical instrument such as a violin. lVhile it is not desired to limit the invention to any particular size of sound box the same is preferably of the size of which a cello is Mounted upon the sound box 27 in any suitable manner are the bridge members 28 which are preferably made of vulcanized fiber or similar material, the same being preferably secured to the sound box .there will be no vibrational movement of the rods 33 relative to the b dge members 28. It will be noted that a br ge member 28 is provided substantially at each end of the rod-like members 33 and substantially midway of the length thereof and that a large number of said rod-like numbers are provided which are all of substantially the same length and are arranged substantially in parallelism. In the embodiment shown there are sixteen ot' the rod-like members 33 shown although this number may be varied it desired.

The sound. box 27 also has the rod supporting members 34 and 35 secured thereto by any su table securing means such as the screws Sftand 37 respectively. The members 34 and 35 are preferably made of vulcanized libcr or similar material and are provided 4 with openings therein to snugly receive the rod-like members 38 which are similar to the rodlike members 32 but which are consideu ably shorter than the members 32 and extend transversely thereto at an oblique angle. While the members 38 are shown as being graduated in length, this is not absolutely necessary, as this adds merely to the appearance of the device. The member 35 is also shown as having a curved lower edge 39 but this is also not absolutely necessary as it merely improves the appearance of the dc vice and avoids sharp corners. members 38 are preferably driven into the openings in; the members 34 and 35 so as to fit therein in such a manner that there will be no vibration of said rod-like members 38 relative tothe members 34 and 35. Secured to the member 35 by any suitable ineans such as the screw 39 is the stylus holder 40 in which the stylus 41 is secured in any suitable manner as by means of the usual clampingscrew 42, and the stylus 41 engages with the grooves of a phonographie sound reproduc- The r0d-like ingrccord 43 in the usual manner; The set of rods 38 and the set of rods 33 are firmly connected together so that vibrations set up in the stylus 41 due to the record 43 are transmitted from the rods 38 to the rods 33. The means for securing said sets of rods together comprises abar of fibrous material 44 which is firmly secured to the rods 38 by driving the rods 38 through openings therein so that therewill be no vibration of the member44rclative to the rods 38. A similar member 45 is provided with openings 46 which snugly receive the rods 33, the rods 33 being also preferably driven into position in'the openings 46. The member 45: is also preferably made of fibrous material such as vulcanized fiber and the members 44 and 45 are firmly secured together by means the screw 47, a spacing member such as the washer 48 being provided between the mem bers 44 and 45.

A; plurality other like members of leather 49, 56) and 51 are mounted upon the rods 33 having openings therein receiving said bars and being sl dable on the barsto any desired position thereon. A similar member 52 of leather; engaging with the bars 38 in a sim-i ilar manner. is provided for the setof bars being also adjustable on said bars 38. The members 49', 50 51 and 521 are provided for adjustment on: the members 33and 38 so as to control the vibration oii the same in a manner to break up the natural period ofvibration of the rods 33 and 38 respectively,"

thus preventing such individual natural vibration of theirods from bein set up due to transmission of the vibrations set up by the stylus 41 therethrough and preventing injury to the tone of the reproduced soundby such vibrations due to the natural period of vibration of the rod-like members themselves. The sound box 27 is provided with the usual opening 53 therein.

,t will be obvious that vibrations set up in the needle or stylus 41 will be transmitted to the member-35 and from themember'35 to the rods 38 and from said rods 38 to the sound box 27 and to thc rods 33 through; the members 44 and 451 and the screw threaded clamping member 47, and that the vibration of the rods 38: will be transmitted to the sound box through the bridge members 28., It has been found, as stated above, that this arrangement produces an unusually desirable quality of tone, especially in connection with instrumental music and produces-a particularly liaithful reproduction: of the tone quality of stringed musical instruments;

h at I claim and desire to secure by Lea ters Patent is:

1. A sound reproducing device comprising a sound box, a stylus supporting member, and a plurality of sets of rigid, elongated vibratory members mounted on said sound box one of said sets being secured to the lie stylus supporting member and the other set being connected with said first set.

2. A sound reproducing device comprising a sound box, a stylus supporting member, and a plurality of sets of rigid, elongated, metallic rod-like members mounted on said sound box, one of said sets being attached to the stylus supporting member and the other set being rigidly connected with said first set.

3. A sound reproducing device comprising a sound box, a plurality of sets of rigid elongated vibratory members mounted on said sound box, said sets being rigidly at,- tached to each other to transmit vibration from one of said sets directly to the other set and from the other set to the sound box, and means for vibrating said members.

4. A sound reproducing device comprising a sound box, a plurality of sets of rigid elongated vibratory members mounted on said sound box, one of said sets being rigidly connected to the other set at points inter mediate the ends of the sets to transmit vibration from one of said sets to the other set, and means for vibrating said members, the members of one of said sets being appreciably longer than the members of the other set.

5. A sound reproducing device comprising a sound box, a st lus supporting mem ber, a plurality of rigid elongated vibratory members connected with said stylus and mounted on said sound box, and means comprising elongated rigid elements for firmly securing said vibratory members to said sound box at spaced points.

6. A sound reproducing device comprising a sound box, a plurality of sets of rigid elongated vibratory members mounted on said sound box, said sets being connected to transmit vibration from one of said sets to the other set, means for firmly securing the vibratory members of aid sets to said sound box at spaced points, and means for vibrating said members.

7. A sound reproducing device comprising a sound box, a stylus supporting member, a plurality of rigid elongated vibratory members rigidly connected with said stylus and mounted on said sound box, and adjustable mean engaging said elongated members to prevent the individual natural vibration of said members.

8. A sound reproducing device comprising a sound box, a stylus supporting member, a plurality of rigid elongated vibratory members rigidly connected with said stylus and mounted on sa'd sound box, and a plurality of members adjustable lengthwise of said elongated members to prevent the individual natural vibration of said members.

9. A sound reproducing device comprising a sound box, a plurality of sets of rigid elongated vibratory members mounted on said sound box, said sets being connected to transm t vibration from one of said sets to the other set, means for vibrating said members, and adjustable means engaging said elongated members of each of said sets to prevent individual natural vibration of said members.

10. A sound reproducing device comprising a sound box, a plurality of sets of rigid elongated vibratory members mounted on said sound box, said sets being connected to transmit vibration from one of said sets to the other set, means for vibrating said members, and a plurality of members adjustable lengthwise of said elongated members to prevent the individual natural vibration of said members.

In testimony whereof I afiix my signature.

EERT U. IWWERKS. 

